# 作业
# 第一题
str1 = "python cainiao 666"
task = str1.find("o")
# print(task)

str_two = 666
str_two += 2
str_two -= 3
# print(str_two)

# 第二题
# price = input("请输入橘子的价格")
# weight = input("请输入橘子的重量")
# price1 = int(price)
# weight1 = int(weight)
# # print(type(weight1))
# res = weight1 * price1
# print(res)


price = int(input("请输入橘子的价格"))
weight = int(input("请输入橘子的重量"))
print(price * weight)

# # 第三题
# my_hobby = "Never stop learning!"
# # 截取从位置2-位置6的字符串，含位置6
# print(my_hobby[1:6])
# # 截取完整的字符串
# print(my_hobby[::1])
# # 从索引3开始，每2个字符中取1个字符
# print(my_hobby[3::2])
# # 截取字符串末尾的两个字符
# length = len(my_hobby)
# print(length)
# print(my_hobby[18:20])
# # 字符串倒序
# print(my_hobby[::-1])